This application is related to application Ser. No. 07/901,036, filed on even date, and based on German Patent Application P 41 20 380.1; application Ser. No. 07/901,595 filed on even date, and based on German Patent Application P 41 20 379.8.
The present invention relates to a locking arrangement between a selector lever of a transmission and an ignition lock of a motor vehicle. The selector lever is held so that it can be swivelled into various positions and the selector lever, in a parking position, is lockable via a locking part. This locking part can be manually shifted via a button arranged on the selector lever. This locking part has a locking pawl which, by way of a flexible linkage interacts with the ignition lock in such a manner that the ignition key can only be pulled off in the inoperative position of the ignition lock when the selector lever is in the parking position and the button is not operated. The locking pawl, in this case, locks the locking part, so that the selector lever is locked in the parking position until after the ignition key has been rotated in the direction of a first operative position, whereby the locking pawl releases the locking part.
European Patent Document EP-0 307 846 A1, shows a locking arrangement of the above-mentioned type in which a button is arranged on a selector lever which is held on a selector lever block so that it can be swivelled into various positions. This button is to be operated manually and actuates a slidable locking part on the selector lever which engages in a recess of a gate assigned to the parking position. When the button is not operated, the selector lever is therefore locked in this parking position.
By way of a flexible linkage, an ignition lock acts upon a locking pawl disposed in the selector lever block in such a manner that the ignition lock with the ignition key can only be brought into an inoperative position permitting the pulling-out of the key when the selector lever is in the parking position and the button is not operated, in which case the locking pawl locks the locking part. On the other hand, the selector lever is locked in this parking position until after the ignition key has been turned in the direction of a first operative position, whereby the locking pawl releases the locking part. The button can then be operated, and the selector lever can be moved out of the parking position.
From the German Patent Document DE-38 42 332 C1, a locking arrangement is known in which a flexible linkage is arranged between the selector lever and the ignition lock. This flexible linkage is subjected to tensile stress at both ends by compression springs which are supported on the housing side. In this case, the spring power of the ignition-lock-side spring is higher than that of the selector-lever-side spring.
The risk of an intentional or unintentional misuse of such a locking arrangement where the ignition key can be pulled out without a locking of the selector lever in the parking position exists particularly when the person operating the motor vehicle can operate simultaneously with both hands the ignition key and the selector lever. This applies, for example, to motor vehicles whose ignition lock is arranged on the side of the steering wheel that is opposite the selector lever.
It is an object of the invention to provide a locking arrangement of the above-mentioned type in which an unauthorized pulling-out of the ignition key, while the parking position of the selector lever is not yet engaged, is avoided under all circumstances.
This and other objects are achieved by the present invention which provides a locking arrangement between a selector lever of a transmission and an ignition lock of a motor vehicle. The selector lever is held so that it can be swivelled into various positions. The arrangement includes a locking part which can be manually shifted by means of a button arranged on the selector lever so as to lock the selector lever in a parking position. A flexible linkage is connected to the ignition lock and has a selector-lever-side end with a locking cam that travels along a moving path. A locking pawl is connected with the flexible linkage and interacts with the ignition lock via the flexible linkage in such a manner that an ignition key can only be pulled out in an inoperative position of the ignition lock when the selector lever is in the parking position and the button is not operated. The locking pawl locks the locking part, and the selector lever is locked in the parking position until after the ignition key is rotated in the direction of a first operative position, with the locking pawl releasing the locking part. The locking pawl has a recess which form-lockingly surrounds the locking part when the button is operated into a first position and the selector lever is in the parking position. The pawl also has a catch hook that engages with the locking cam connected with the selector-lever-side end of the linkage along the moving path of the locking cam such that the linkage is locked and the ignition key cannot be rotated into the inoperative position.
In the parking position of the selector lever, a locking part, which is constructed as a cam part, is form-lockingly surrounded by a recess of a locking pawl. When the button is operated, the cam part holds the locking pawl in a position in which a catch hook of the locking pawl engages in the moving path of a locking cam connected with the selector-lever-side end of a flexible linkage while locking the linkage. The thus locked linkage prevents a turning of the ignition key in the inoperative position of the ignition lock and therefore the pulling-out of the key and, for example, a catching of the steering wheel lock. The form-fitting reaching around by the cam part has the effect that, when the operated button is released, the cam part rotates the locking pawl, so that the catch hook is rotated out of the moving path of the locking cam. The linkage is released and the ignition key can be turned into the inoperative position, and the locking cam is moved on its moving path into a position fixing the catch hook. A pushing of the button will now not be possible because the locking pawl fixed by way of the catch hook holds fast the cam part by means of the recess.
An unintentional or unauthorized pulling-out of the ignition key, when the parking position is not yet engaged, is therefore avoided under all circumstances. When the button is pushed, in the parking position, as well as in all other selector lever positions, a pulling-out of the ignition key is securely prevented by the engaging of the catch hook. The form-fitting reaching around of the cam part causes a forced control of the locking pawl so that, in the event of an intentional pulling-out of the ignition key, the position of the selector lever and the operating of the button is sensed.
In particular, for motor vehicles in which the ignition lock is arranged on the side of the steering wheel situated opposite the selector lever and in which the person operating the motor vehicle can therefore operate the ignition key and the selector lever at the same time, no intermediate position of the ignition lock and of the selector lever can be found in which the ignition key can be pulled out before the parking position is engaged and the button is released.